Development, optimization and validation of an analytical method for the determination of Voriconazole in plasma by High-Performance Liquid Chromatography-Ultraviolet detection: Application for comprehensive Study

OBJECTIVES

Voriconazole is a widely used antifungal agent in clinical settings. However, its use has been associated with neurological side effects in some patients. For this reason, it is crucial to monitor its plasma levels to ensure that they are within the therapeutic range. Thus, in this study, we aimed to develop a simple, fast, and efficient method for the determination of voriconazole in plasma using reversed-phase HPLC-UV. We also aimed to validate the method for its application to routine analysis of immunocompromised patients.

MATERIAL AND METHODS

Plasma samples from immunocompromised patients were subjected to deproteinization with acetonitrile followed by centrifugation. Chromatographic separation was carried out on a C18 column with UV detection at 254 nm in isocratic mode. The concentrations were calculated by comparing peak areas to those of the internal standard, ketoconazole. The method was validated using the accuracy profile, which uses a calibration curve established for the therapeutic range of 1 to 5.5 µg/mL.

RESULTS

The developed method was proved to be rapid by giving a short analysis time for voriconazole at around 5.5 min. Additionally, no interference with the biological matrix was detected. The obtained recoveries were higher than 90%. The accuracy profile showed that the method was accurate and precise for the determination of voriconazole in plasma.

CONCLUSION

The developed method was proved to be simple, efficient, that requires minimal sample preparation. Thus it can be routinely applied for the therapeutic monitoring of voriconazole.

A simple and green LC method for the determination of ibuprofen in milk-containing simulated gastrointestinal media for monitoring the dissolution studies of three dimensional-printed formulations

A fast and green ultra high-performance LC method was developed for the determination of ibuprofen in milk-containing simulated gastrointestinal media to monitor the dissolution of three-dimensional printed formulations. To remove interfering compounds, protein precipitation using methanol as a precipitation reagent was performed. The separation of the target analyte was performed on an C18 column using a mobile phase consisting of 0.05% v/v aqueous phosphoric acid solution: methanol, 25:75% v/v. Method validation was conducted using the total error concept. The β-expectation tolerance intervals did not exceed the acceptance criteria of ± 15%, meaning that 95% of future results will be included in the defined bias limits. The relative bias ranged between ─ 1.1 to + 3.2% for all analytes, while the relative standard deviation values for repeatability and intermediate precision were less than 2.8% and 3.9%, respectively. The achieved limit of detection was 0.01 μg mL^-1 and the lower limit of quantitation was established as 2 μg mL^-1 . The proposed method was simple, and it required reduced organic solvent consumption following the requirements of Green Analytical Chemistry. The method was successfully employed for the determination of ibuprofen in real biorelevant media obtained from dissolution studies. This article is protected by copyright. All rights reserved.

Development and Validation of an HPLC-UV Method for the Dissolution Studies of 3D-Printed Paracetamol Formulations in Milk-Containing Simulated Gastrointestinal Media

Herein, a simple and rapid HPLC method for the determination of paracetamol milk-containing biorelevant media is proposed. The separation of the analyte from the milk-containing biorelevant media was accomplished isocratically using a mobile phase containing 25 mM phosphate buffer (pH = 3.0) and methanol, 80:20, v/v at a flow rate of 1 mL min⁻¹. Following a protein precipitation-based sample clean-up, a thorough investigation of the effect of the precipitation reagent (methanol, acetonitrile, 10% v/v trifluoroacetic acid solution) on the analyte recovery was performed. The matrix effect was assessed in each biorelevant medium by comparing the slopes of the calibration curves of aqueous and matrix-matched calibration curves. The method was comprehensively validated using the accuracy profiles. The β-expectation tolerance intervals did not exceed the acceptance criteria of ±15%, meaning that 95% of future results will be included in the defined bias limits. The relative bias ranged between −4.5 and +3.9% for all analytes, while the RSD values for repeatability and intermediate precision were less than 2.7% and 3.0%, respectively. The achieved limit of detection (LOD) was 0.02 μg mL⁻¹ and the lower limits of quantitation (LLOQ) were established as 10 μg mL⁻¹, which corresponded to 2% of the highest expected concentration of paracetamol. The proposed scheme was utilized for the determination of paracetamol in dissolution studies of its 3D-printed formulation in milk-containing biorelevant media.

Comparative study of three fingerprint analytical approaches based on spectroscopic sensors and chemometrics for the detection and quantification of argan oil adulteration

BACKGROUND

Argan oil is one of the purest and rarest oils in the world, so that the addition of any further product is strictly prohibited by international regulations. Consequently, it is necessary to establish reliable analytical methods to ensure its authenticity. In this study, three multivariate approaches have been developed and validated using fluorescence, UV-visible, and attenuated total reflectance Fourier transform mid-infrared (FT-MIR) spectroscopies.

RESULTS

The application of a partial least squares discriminant analysis model showed an accuracy of 100%. The quantification of adulteration have been evaluated using partial least squares (PLS) regression. The PLS model developed from fluorescence spectroscopy provided the best results for the calibration and cross-validation sets, as it showed the highest R² (0.99) and the lowest root mean square error of calibration and cross-validation (0.55, 0.79). The external validation of the three multivariate approaches by the accuracy profile shows that these approaches guarantee reliable and valid results of 0.5-32%, 7-32%, and 10-32% using fluorescence, FT-MIR and UV-visible spectroscopies respectively.

CONCLUSION

This study confirmed the feasibility of using spectroscopic sensors (routine technique) for rapid determination of argan oil falsification. © 2021 Society of Chemical Industry.

Green reversed-phase HPLC development strategy: Application to artesunate and amodiaquine analysis

A green analytical chemistry strategy is described to develop a reversed-phase high-performance liquid chromatography method for amodiaquine and artesunate analysis using ethanol-based mobile phases. This method development was particularly challenging due to the basicity of amodiaquine and low UV absorption of artesunate, leading to peak asymmetry and detection issues, respectively. UV detection concern was even more challenging due to the baseline drift observed with ethanol in gradient mode. Several green pH modifiers were selected for their ecofriendly character and their impact on peak shape and detection was investigated. The screening of various stationary phases (19 columns) appeared as a relevant and necessary approach to reach satisfactory peak shape of basic compounds. To support the results of this study, some additional compounds related to artesunate and amodiaquine structures were included. Methods were optimized and validated using total error approach with a mobile phase composed of ethanol and 10 mM formic acid using three different stationary phases from different manufacturers, providing flexibility of the quality control approach. Method greenness was assessed using the National Environmental Methods Index, the Green Analytical Procedure Index, and the Analytical Eco-Scale. Finally, artesunate and amodiaquine were successfully analyzed in fixed dose combination tablets.

Green Analytical Methods of Antimalarial Artemether-Lumefantrine Analysis for Falsification Detection Using a Low-Cost Handled NIR Spectrometer with DD-SIMCA and Drug Quantification by HPLC

Two green analytical approaches have been developed for the analysis of antimalarial fixed dose tablets of artemether and lumefantrine for quality control. The first approach consisted of investigating the qualitative performance of a low-cost handheld near-infrared spectrometer in combination with the principal component analysis as an exploratory tool to identify trends, similarities, and differences between pharmaceutical samples, before applying the data driven soft independent modeling of class analogy (DD-SIMCA) as a one-class classifier for proper drug falsification detection with 100% of both sensitivity and specificity in the studied cases. Despite its limited spectral range and low resolution, the handheld device allowed detecting falsified drugs with no active pharmaceutical ingredient and identifying specifically a pharmaceutical tablet brand name. The second approach was the quantitative analysis based on the green and fast RP-HPLC technique using ethanol as a green organic solvent and acetic acid as a green pH modifier. The optimal separation was achieved in 7 min using a mobile phase composed of ethanol 96% and 10 mM of acetic acid pH 3.35 (63:37, v/v). The developed method was validated according to the total error approach based on an accuracy profile, was applied to the analysis of tablets, and allowed confirming falsified drugs detected by spectroscopy.

Calibration Curves in Quantitative Ligand Binding Assays: Recommendations and Best Practices for Preparation, Design, and Editing of Calibration Curves

The accuracy of reported sample results is contingent upon the quality of the assay calibration curve, and as such, calibration curves are critical components of ligand binding and other quantitative methods. Regulatory guidance and lead publications have defined many of the requirements for calibration curves which encompass design, acceptance criteria, and selection of a regression model. However, other important aspects such as preparation and editing guidelines have not been addressed by health authorities. The goal of this publication is to answer many of the commonly asked questions and to present a consensus and the shared views of members of the ligand binding assay (LBA) community on topics related to calibration curves with focus on providing recommendations for the preparation and editing of calibration curves.